


Jure Fratris

by Anonymous



Category: Horus Heresy - Various Authors
Genre: Alternate Universe - A/B/O, Breeding, Implied Mpreg, M/M, Multiple Orgasms, Restraints, Switching
Language: English
Status: Completed
Published: 2018-12-30
Updated: 2018-12-30
Packaged: 2019-09-30 21:33:39
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 1
Words: 4,081
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17231588
Author URL: https://archiveofourown.org/
Summary: In the right of his brother.Wherein Horus receives an unusual missive from Fulgrim.





	Jure Fratris

**Author's Note:**

> Set in some reality where Ferrus is either not killed or somehow revived, takes place during the first part of _Vengeful Spirit_ by Graham McNeill.

The Sixty-Third had been garrisoned at Dwell for a little over a week when the Twenty-Eighth came to meet them. Had their forces been meeting in the time before, there would have been a great fête for the reunion, all the pomp and circumstance which the Emperor's Children insisted on followed by the friendly brawls which the Sons of Horus -- then, when they were still known as the Luna Wolves -- enjoyed. But those days were now a distant memory, covered in the soot of civil war.

Fulgrim stayed in his flagship and, outside of communication between the Navigators, made no effort to communicate with his brother. Rather, some hours after it was apparent there would be neither fête nor theatrical production, a delegation came from the Twenty-Eighth to the Sixty-Third.

Although a full squadron of Fulgrim's personal guard had been sent as representatives, not even Eidolan was a part of the delegation -- and no captains, so far as was listed on the official embarkation request -- and so Horus, in part wishing to be polite and in larger part carefully hedging his bets (for Fulgrim, while still a brother, was not at all like the brother he remembered, especially not as Istvaan), deigned to receive the delegation in a similar fashion. There was Ezekyle, the First Captain, and his accompanying Justaerin Guard, but only five instead of the usual ten. His equerry Maloghurst was there as well, a near-permanent spectre in the Lupercalian court, but there was no honour guard beyond that, no spectators for their meeting.

"Warmaster," the head of the Phoenix Guard addressed, dropping to a kneel before him. His brethren did the same. "My lord Primarch Fulgrim has a message for you."

"Very well," Horus stood and walked over to the legionary. A dataslate was placed in his hand. In earlier times, he might have openly mused -- perhaps even light-hearted complained -- why Fulgrim did not choose to speak with him personally. But these days gave little reason for humour and so he kept his peace.

The dataslate was genelocked and required that he brush his lips against the surface. As soon as he had done so, the information was neatly presented, illuminated in a way which Maloghurst, standing ever behind him, could not read. It was without a doubt a message from Fulgrim, filled with the usual pleasantries even his changed self could not divorce from and though Horus could read the series of lines (no less than five) within seconds, comprehension came at a slower rate.

He swallowed and reread the missive, then crushed the dataslate beneath his heel.

Both sets of legionaries tensed. Ezekyle reached for his sword. He would have to have words with Ezekyle soon; they were short enough on allies, there was no chance in hell he would be turning his blade on Fulgrim, not even for his most recent transgression. Instead of a headache, Horus felt blood rushing through; his heartrate was accelerating in disbelief, yes, but also anticipation.

"I understand," he told the head of the Phoenix Guard. "Tell my brother it will be done."

-

A second delegation from the Twenty-Eighth arrived less than an hour after the first. Fulgrim must have known what he was asking, he needed to have been certain that Horus would agree to it. And still, Horus could not believe his eyes, when he saw his third-to-be-found brother in the flesh at the center of said delegation.

Ferrus Manus was dressed like a Chemosian oligarch. He was swathed with rich trailing robes of red and purple, decorated at the edges with silver and gold. Fulgrim had sent him off with a king's ransom; Horus was certain the precious metals and gems on his person -- on his fingers and ears and about his neck -- were enough to buy a Terran duchy.

There was a hush of silence at the sight of him. With the second delegation, Horus could have spared no expense. This was a brother, a brother Primarch, and though he was -- presumably -- still an enemy, it was still paramount that he be treated like an honoured guest. The whole First Company was present, as well as his newly-formed Mournival, and the newcomers from the Emperor's Children were similarly laureled this time around with the First Captain Julius Kaesoron leading this section of Phoenix Guard.

There were rumours that the Tenth Primarch still lived. Horus had heard some of them himself, but he had not heard anything from Fulgrim. But now, to see Ferrus in the flesh -- and he was certain it was Ferrus, for he could sense him as clearly as a blind man might nonetheless tell the difference between night and day -- was something else entirely.

He stood up and parted the waves of men, reaching for Ferrus with outstretched arms.

"Brother," he greeted, embracing him before both groups of men, "How good it is to see you again. Welcome, welcome back."

Against him, Ferrus stiffened. He made no motion to return the gesture and Horus sensed but could not see that the other had been bound, somehow. His limbs were leaden, as if held still by invisible shackles, and while he could stand and walk, there was little chance of him lifting his arms much less recusing himself from the procession.

This is war, he reminded himself. This is what your war has come to, his conscience whispered back.

He stepped away from Ferrus, looking briefly into his brother's famed silver eyes before looking back at their spectators.

"Thank you for making the journey," he told Captain Kaesoron before addressing his own men: "And thank you for witnessing our reunion. It has been some time before I have spoken with our Gorgon so you will have to excuse us."

It was a half-order given in his usually pleasant tone, but Captain Kaesoron was used enough to such commands. He dropped to a kneel, along with the rest of his guard, and murmured thanks. The Sons of Horus did the same and within minutes, the hall was cleared of man and Astartes alike, leaving the two Primarchs beneath its towering spires.

Horus looked to his throne. There was a box to the left of his armrest which held the skull, the skull that Fulgrim had purported to be Ferrus' but could not possibly be his, not when he was standing right before him, irritated and clearly holding his tongue, as if the two of them had been tasked with leading the Imperial brigade, back when they had been brothers four.

"Ferrus," he breathed, grasping at air around him.

"Horus," Ferrus answered at last.

Horus lost himself for a moment then, so flooded was he with relief. It was a blessing that he had ordered everyone else out, for it was unbecoming to fall to his knees in his own hall, closing his eyes and digging his fingers against the marble tiles. Ferrus lived. He spoke. He breathed. He still stood on the opposite side, as evidenced by how Fulgrim needed to keep him chained, but he still lived.

Still on his knees, Horus looked up to the other looking down at him. There was the same irritated expression, as if he had been sent on a fool's errand. The problem with Ferrus was that he was always thinking something, but he would often think ten thousand things before saying a single one. He had no idea how Fulgrim managed to regularly converse with him -- outside of the most direct and necessary of questions (which did not include 'Where do you plan to move your troops?' because Ferrus presumed, albeit correctly, that Horus would know regardless of what he said and so there would be no reason to say anything) Ferrus turned taciturnity into its own virtue.

"I grieved for you," he said at last.

There was a momentary softening in Ferrus' eyes, which was the equivalent of tears shed for anyone else, and it was as if Ferrus were the older sibling for a moment. And then it was gone and in its place, something like a darkened pity.

"And I grieve for you, still," Ferrus answered.

Horus swallowed and pushed himself up. Ferrus towered over most of their brothers save for Vulkan, and on their first meeting, even Horus had felt cowed. He, who had always been a head taller than everyone else, was suddenly second place. Ferrus must have felt something similar -- all of their brothers must have felt something similar -- when the decision for Warmaster was given. But Ferrus, first among them, had given his congratulations and thrown his full support behind Horus. And his men too, had been closer with the Sixteenth than any other, save for the Third.

"Come," Horus said, placing a hand on his brother's back, "These halls are too formal and their ghosts too many. There are fewer ears in my private quarters and I would have words with you."

-

When seated across from the one brother who understood war as well as him, who heard the incomprehensible melody that drifted across the stars and on each battlefield, Horus could feel his carefully cultivated persona slip away. He still remembered encountering Ferrus for the first time. He was the one who had noticed him, who had sensed the presence of a brother Primarch out on the Medusan wastelands and the Emperor had tasked him with finding the source.

Though Ferrus was not the first nor the last, he was the first one that made Horus see the potential and value of having fellow Primarchs. Before, and with Russ especially, it had been one frustration after another. Am I not good enough, he had kept himself from saying, why was I made to have brothers, why did you need so many sons?

And so it was that all his plans, machinations enough to make Maloghurst swell with pride, fell to pieces. He had entertained thoughts of playing the long game, of perhaps dragging it out so slow and steady that Fulgrim might come over, demanding to know what was taking them so long.

Horus opened his mouth to speak and found himself experiencing the same dryness of mouth and accompanying palpitations which his own men so often displayed before him. It was ridiculous, but it was Ferrus -- Ferrus, who he had missed and mourned and privately grieved and berated, in the flesh, effectively back from the dead -- and he could do nothing more than ask: "Do you know what Fulgrim has sent you here for?"

Ferrus nodded once and once was enough. Horus swept the wine glass and bottle away, sending both crashing to the floor, and he surged forward, seizing his brother by the face and kissing him with an embarrassingly chaste fervency.

It was a good fifteen paces from the table to the bed but he pushed and Ferrus went. Soon, the two of them were toppled against the sheets and he had Ferrus pressed up against a mattress specially designed to withstand their might.

"Ferrus," he said again, straddling against the other as he worked to undo the fastenings on both their garments. Though they were entirely without armour -- or else they would have had to call for a dozen slaves to disrobe -- there were still too many buttons and ties and self-saving folds. When Horus was more or less out of his own clothes and working on Ferrus', he discovered the source of his brother's imprisonment. It was the jewelry he had been bedecked with.

"Throne of Man," he cursed despite himself when he had trouble removing the necklace. "This thing must weigh two tonnes, how do you even manage to stand?"

Ferrus said nothing but made a face, no doubt more annoyed by their states of undress and what was yet to come than the impossibly dense collar that had been made to look like a necklace about his neck. The earrings and rings were similarly weighted and Horus made sure to set them on the floor, lest they collapse the nearby cabinets or worse, the bed.

"You have fallen as far as him," he sighed, when he was freed from the last of his shackles.

Horus laughed, still straddling the other, and grinded his hips against Ferrus, preening. "Does my form not please you, brother?"

"We were not made for such things."

"That is true," Horus conceded, quirking his lips. When Fulgrim had come to him after Istvaan, his eyes had been burning with fury, fury at how 'wretchedly small-minded and straight-and-narrow' Ferrus could be and how 'utterly blind' he had been to the larger scheme of things. Horus found himself sympathizing with Fulgrim then, but grinned nonetheless, for Ferrus was here, beneath him, and it was not often that such intimate opportunities for persuasion came about. "And yet, the ability remains."

Ferrus would have likely protested or given him another pitying and dismissive glance, had Horus not doubled down, sliding off the bed and onto his knees and taking Ferrus' unclothed but still-soft length into his mouth with a single breath.

Horus closed his eyes, concentrating on working the shaft with his tongue and inching his lips higher and higher until his nose touched coarse black curls, until he could feel Ferrus against his throat. He swallowed and the motion made Ferrus buck his hips and groan and most importantly harden. His silver hands, no longer weighed down with those half-dozen rings, were against Horus' head, scrabbling against hair that hadn't been there for years, not since he had shorn his childhood sidelock. His mouth was where it had been when Ferrus came and Horus smiled, drinking it down, before pulling himself back up and treating Ferrus to the sight of him.

Horus knew that his eyes were glistening with something mad, some dark want that Fulgrim too had been enraptured by, and Ferrus could not hide the shiver that ran through him at the sight, not could he stop the blush that spread across his face.

"Have you -- wanted this -- long?" he asked, straining for the right words as Horus stroked him tenderly to hardness yet again.

"The thought had not occurred to me," Horus confessed. Then he lifted his hips and sank himself down on Ferrus' newly-coaxed erection. The two of them hissed at the contact; in his usual Cthonic bluster, Horus hadn't bothered with preparation and Ferrus was caught off-guard, for --

"It's meant to be the other way around, you fool," he blustered, though the force of his complaint was lost in his own expression, caught between disgruntlement and pleasure.

"Oh you will get yours soon enough, I promise," Horus answered, canting his hips a couple times. He set his palms against Ferrus' bare chest and threw his head back, truly riding the other. Neither of them could last long, Ferrus in particular came a second time within a couple thrusts, grunting and giving a couple jerks of his own hips. Horus wrapped a hand about his own erection, rolling his hips as Ferrus spurted in him before working himself to climax. He splattered between the two of them, against Ferrus' chest and face and on his own hand. And then, with his breath not yet caught and Ferrus' still-softening cock wedged inside him, he leaned forward and licked the wayward drops off of his brother's face.

A silver hand was against his cheek immediately.

"You're disgusting," Ferrus grumbled, turning to the side so as to shove Horus off. Horus went without a fight, breaking into amused laughter despite himself, as if they were newly-acquainted brothers playing the charge of armies in the Emperor's private apartments.

"I can't believe it," he said again, wiping his hand against the sheets before bringing it to Ferrus' face. "You're here. You _live_. But how?"

He was a fool indeed to expect an immediate response. Instead, Ferrus closed his eyes, as if to savour the contact, before he lifted his hand to brush Horus away. When he opened his eyes again to sigh, that same disgruntlement had surfaced yet again.

"By dint of those Warp magics of yours, what else?" was his oddly bitter reply.

Horus thought of Davin and then Istvaan, of the Mausolytic District of Dwell and of Molech. The other three were vivid memories, but Molech... even the name seemed unimportant. They would be taking off soon, within the week if Maloghurst's readings were followed, and there was little chance of the Twenty-Eighth following. He had no idea what Fulgrim must have sacrificed to the True Gods in order to revive Ferrus, in a manner as perfect as such, but here he was, whole and in the flesh, though in possession of enough independence so as to remain turned away from their cause.

He closed his eyes for a moment, imagining how many times Fulgrim must have attempted to couple before coming to terms with the grim limitations -- with the embarrassing defect -- of his own genetic structure. Perhaps he had always known, even before they had shirked off their Imperial shackles. Either way, it was simultaneously sickening and heartening, that he might send Ferrus -- so best-beloved that even death could not part them -- to him, for the express purpose of coupling. Just the thought of it sent a spark to his prick and when he opened his eyes, Ferrus was still there, still looking at him, and he found himself surprised, that the other had made no attempt to leave. Of course, his lack of dress might have been an issue, but were their positions reversed, Horus is certain he would have tried.

He sighed too, at once melancholic and wanting. He wanted, that much was certain, but it would be over as soon as it had started and there was the galaxy after that, of course. Ferrus had said it best, back when they were on the same side: their kind was not made for hearth and home.

"What sort of face," Horus started, sitting up and reaching for Ferrus anew, "Do you think our brother will make, when I send you back to him?" He kissed Ferrus fully, still with neither teeth nor tongue, before trailing his lips down his brother's neck onto the shoulder. His hands traced their way across the planes of his bare body and Ferrus leaned into his touch. Horus was pleasantly surprised to feel him spread his legs for better access when Horus moved to graze his entrance.

"He is a man possessed," Ferrus answered, lifting his hips as Horus slid a finger inside of him. "And you have fallen just as far."

Horus chuckled at that before giving a hum of approval as Ferrus clenched his eyes and fists, as he grit his teeth. "I long to see his expression," he continued, even as he felt around the other, circling, circling until -- there -- he rubbed at the spot that made Ferrus buck away and then against him, the spot that made him clutch at Horus' upper arms with a helpless whimper. The sound alone could have pushed him to the edge. He continued his ministrations for some time, drinking in Ferrus' heady breaths and moans, until he was three fingers into the other -- a girth impossible for anyone other than a fellow Primarch -- and Ferrus was leaking and twitching in his lap.

With but a nudge, the second-largest of his brothers keeled over, curled forward on his knees and elbows with his arse in perfect display. Horus did not have the patience to enjoy the view, following right after. He wrapped his hand about himself, guiding his member in, and clenched his own teeth, hissing a second time, at the sweet tightness that soon followed.

"I wish to see it," he said again as he leaned forward so that his chest was pressed against Ferrus' back, so that his hands were covering Ferrus' fists, "When I send you back, filled with my seed and covered with my sweat, to give birth to my child so that your new sons may be mine." Ferrus moaned, or perhaps sobbed, but what mattered was that he ground his hips back against Horus and it was all the prompting Horus needed to fuck him in earnest against the mattress with a lack of delicacy that could only be afforded amongst his fellow Primarchs.

-

As all things were, it was as he said. As soon as they finished coupling and calmed themselves sufficiently so that their breaths and heartrates were stable once more, they had but enough time for a visit to the baths before the servants and slaves were fussing over them. They were dressed in full regalia soon enough, Horus with his wolf pelt and cape and Ferrus with his Chemosian robes. A full team of servitors were insufficient for the jewelry and Horus himself had to lift the trinkets up to secure them around a not entirely unwilling but certainly not happy Ferrus.

They did not speak much then. Well, Horus was quite jocular, as he tended to be after congress, but Ferrus had retreated to monosyllabic responses.

Within an hour they were dressed to the nines and standing across from one another with their respective delegations in the backdrop. Horus felt something leap from his chest to his throat at the sight of Ferrus and it surprisingly enough had nothing to do with what had just transpired. So, right as Ferrus was to be escorted away onto the waiting Stormbird, he reached for his brother, catching even Ferrus off-guard in the suddenness of his gesture.

Before his men and Fulgrim's men, he kissed both of Ferrus' cheeks, much like how Fulgrim himself might have done in the days long since.

"It pleased me to see you once more," Horus said, flashing a careful smile at Ferrus, the same one he had shared after their first meeting. He reached out to touch his cheek and thought he saw a flash of tenderness in his brother's stormy expression.

Ferrus pursed his lips, no longer able to return either gesture, before he too deigned to speak.

"Be well, brother," he said, "You've a long way yet to fall." He turned and the Phoenix Guard surrounded him, ushering him into the waiting gunship. Horus stood at the embarkation deck for some time after that, until the ship was out of sight entirely, on its way to the Pride of the Emperor, docked somewhere in the moon's shadow.

He returned to his quarters and asked for peace and quiet, which was gladly given as no one -- not even Maloghurst -- knew what to make of the abrupt and public exchange between the two of them. Ezekyle would be ranting soon enough and the rest of the Legion was already itching to be off. Dwell was theirs and right after it, Molech.

The servants had left their mark in the room. They had set the fallen wine bottle back on the tableand replaced the pair of shattered glasses as well. Horus chuckled at the sight, seating himself in his usual spot before pouring two glasses of wine. He took one and tapped it against the other before draining it, turning to look out the window, where the outline of the flagship of the Twenty-Eighth could be seen against the outline of daybreak on Dwell.

He poured himself a second glass and raised this one to the sight.

"You are still the better, dear brother," he said, and he did not know if he was speaking of Fulgrim or Ferrus or both. Whether it was Ferrus' capacity for understanding and acceptance, acceptance of the grimmer darker things which they could no more fight than flee, or Fulgrim's utilitarianism and, in spite of his maddened transformed state, ability to sacrifice, in the face of love. If it came to it, and Horus did not that doubt that still could come to it, he did not know if he could do the same as Fulgrim had done, to keep an enemy brother, along with his legion, alive in such a manner.

Then he drank that glass too and retired to his charts and figures. Though everything which was cast aside or overturned had now been put back in its proper place still, Ferrus' scent lingered. As he was leafing over the old Hardan logs -- the longest time his Legion had spent in the company of the Tenth -- a curious nostalgia seeped into him. After Molech, Horus decided, he would pay the Emperor's Children a visit. After Molech, there would be time yet.


End file.
